External-circuit connecting and packaging structure

ABSTRACT

There is disclosed a method of connecting an external circuit, including the steps of disposing between an electrode for connecting the external circuit connected with an electrode for driving a liquid crystal panel and an external circuit electrode connected with the external circuit, a film comprising an insulating resin containing conductive particles dispersed therein, and applying a pulse voltage to a heat tool under the pressure-applied state.

This application is a division of application Ser. No. 186,943, filedApr. 27, 1988 now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of connecting an externalcircuit of a liquid crystal panel, and more particularly to a connectingmethod suited for connecting an external circuit for a ferroelectricliquid crystal panel, and a packaging structure thereby formed.

2. Related Background Art

Hitherto a method has been developed for mutually connecting FPC (aflexible printed-circuit substrate) and wiring substrates (glass epoxysubstrates, glass substrates, ceramic substrates, FPC, etc.) in whichthey are connected by thermocompression bonding of a film-shapedanisotropic conductive film comprising a conductive materialincorporated by dispersion in an insulating resin. Particularly inrecent years, in the field of image display units, such as liquidcrystal display devices and EL display devices that can replaceconventional CRT, or in the field of image reading units such as closecontact image sensors of continuous length integrally formed usingamorphous-Si or the like as sensors that can replace conventional CCD,the connecting method using the anisotropic conductive film havinghigh-density resolution is widely used.

Also frequently used as FPC are film carrier tapes on which IC chips canbe directly mounted. These film carrier tapes have a wiring function formaking connection to image display devices or image reading devices andalso have a function that enables achievement of rationale assemblyprocesses.

However, in the display panels connected with external drive circuitsaccording to a conventional connecting method, the resistance becomes solarge that a large voltage is required for driving liquid crystalpanels.

FIG. 9 illustrates a cross section of a conventional film carrierpackaging structure 50, wherein a copper foil 53 constituting aconductive material pattern is bonded on a flexible insulating film 51with the use of a bonding material. At the inside of a device hole 55bored in the flexible insulating film 51, an inner lead-bonding area 56is formed in the shape of a finger to make a connection with asemiconductor device 54, at which the semiconductor device is connected.

This film carrier 50 is joined by thermocompression bonding on atransparent conductive film 59 of ITO or the like, formed, for example,on a glass substrate of a liquid crystal display device, with the use ofan anisotropic conductive film 57 comprising conductive particles suchas metal particles dispersed in an adhesive.

However, the above conventional film carrier packaging structure has theproblems discussed below.

(a) In recent years, liquid crystal display devices have come to be usedas large screen displays replacing conventional CRTS, and liquid crystaldisplays of, for example, 640×400 dots or more have come to be used inpersonal computers and word processors. In addition, there areincreasing demands for making screens larger, for increasing the degreeof precision and for generating colored images.

In instances where driving ICs are connected to these large screenliquid crystal displays, a packaging structure packaged by theanisotropic conductive film by use of the film carrier system asmentioned above has recently come to be often used. Known anisotropicconductive film are, for example, CP-2132 (a resin compositioncomprising a styrene-butadiene copolymer and solder particles disposedtherein) available from Sony Chemicals Corp., AC5052 (a resincomposition comprising a styrene-butadiene copolymer and Au-plated resinparticles disposed therein) available from Hitachi Chemical Co., Ltd.,and these can have a connection resolution amounting to 5 lines/mm (200μm pitch).

Now, in addition to the demands for making screens larger, increasingthe degree of precision higher and generating colored images, there arealso demands for increasing the density and narrowing the pitch ofpicture elements of the liquid crystal displays. In making screenslarger, a delay in signals from the driving ICs may occur owing to anincrease in load impedance of the transparent conductive film on theglass substrate of the liquid crystal display, resulting in a loweringof display quality levels. In order to prevent such a lowering ofdisplay quality levels, a system has been devised in which, as shown inFIG. 10, the patterns of the transparent conductive film 59 are drawnfrom the central part of a screen to both sides of the glass substrate58, and the film carriers 50 for the driving ICs are connected to bothsides thereof. There are also demands for making the pitches of pictureelements narrower, for example, 8 lines/mm (125 μm pitch) or 10 lines/mm(100 μm pitch), in regard to making a degree of precision higher andgenerating colored images, but, as mentioned above, there is at thepresent time a limit of about 5 lines/mm (200 μm pitch) in packagingfilm carriers with the use of the anisotropic conductive films.Therefore, for example, as shown in FIG. 11, the patterns of thetransparent conductive film 59 on the glass substrate 58 are alternatelydrawn to both sides of the glass substrate 58 in a zigzag fashion toreduce the pattern pitch to a half, and the film carriers 50 for drivingICs are connected to both sides thereof.

However, when it is attempted to package the driving ICs on both sidesof the glass substrate 58, as mentioned above, the following problemoccurs. Assume that, as shown in FIG. 12, the liquid crystal pictureelement driving output of a driving IC 71 to be packaged at one side(the left-hand side in the drawing) is designed to be scanned from 1 tothe direction of an arrow as shown in the drawing. When an identicaldriving IC 71 is packaged at the other side (the right-hand side in thedrawing) as shown in FIG. 13, the direction of the liquid crystalpicture element driving output of the driving IC 71 becomes as shown inan arrow in the drawing, resulting in reversed scanning directions onboth sides of the glass substrate 58 to make it impossible to use thesame driving ICs. For this reason, it becomes necessary to design thedriving ICs 71 so as to have an output capable of being scanned in bothdirections, or to use two type of quite different driving ICs (itfollows that four types are required since in a liquid crystal displaythe driving ICs are required respectively for upper and lower two sheetsof glass substrates), thus increasing the cost for the driving ICs andcomplicating the carrier-packaging processes.

The following problems also occur. If the above-described manner ofpackaging as shown in FIG. 9 is used, a high temperature of from 150° to250° C. is applied to the flexible insulating film 51 of polyimide orthe like formed by hot pressing for the thermocompression bonding whenthe anisotropic conductive film 57 is thermocompression bonded. For thisreason the flexible insulating film 51 undergoes, owing to thedifference in thermal expansion coefficient between the flexibleinsulating film 51 and glass substrate 58, thermal expansion at the timeof the thermocompression bonding. As a result, film 51 shrinks after thethermocompression bonding. This causes slippage between the film 51 andthe glass substrate 58. Such slippage is generated in the anisotropicconductive film 57 or a stress is applied thereto to bring about anincrease in connection resistance and a lowering of connection strength,resulting in a lowering of reliability in the packaging of filmcarriers.

(c) Additionally, the following additionally problems also occur: At thetime of the thermocompression bonding, it is actually desirable to applyheat to the anisotropic conductive film in the range of from 130° to180° C. (variable depending on manufacturer's products) with theprecision of about ±5° C. However, in the conventional packagingstructure heating is carried out by means of a hot press for thethermocompression bonding through the flexible insulating film 51 of thefilm carrier 50. As a result, this flexible insulating film may work asan thermal insulating material, so that it is difficult to control thethermal energy to be applied to the anisotropic conductive film; alsoheating is carried out for a long time.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method of connectinga liquid crystal panel, that can overcome the above disadvantages, andset the resistance of the connecting area to a sufficiently low value.

Another object of the present invention is to eliminate thedisadvantages in the above prior art, to make it possible to packagefilm carriers for driving ICs on both sides of a substrate, and at thesame time to provide a film carrier packaging structure that can preventthe reliability of connection from being lowered because of the slippageor stress caused by the difference in the thermal expansion coefficientbetween the flexible insulating film and the substrate to be connectedthereto, to make it easy to control the heating temperature uponthermocompression-bonding, and to shorten the heating time.

According to one aspect the present invention relates to a method ofconnecting an external circuit, comprising disposing between anelectrode for connecting the external circuit connected with anelectrode for driving a liquid crystal panel and an external circuitelectrode connected with the external circuit, a film comprising aninsulating resin containing conductive particles dispersed therein, andapplying a pulse voltage to a heat tool under a pressure-applied state.

The present invention also relates to a film carrier packaging structurecomprising an outer lead-bonding area and inner lead-bonding area of aconductive material pattern formed on a flexible insulating film,wherein the outer lead-bonding area of a film carrier, extending fromsaid flexible insulating film in the shape of a finger, is disposed soas to face a wiring substrate with the interposition an anisotropicconductive film, the outer lead-bonding area beingthermocompression-bonded to the wiring substrate by heating throughanother flexible insulating film thinner than the first-mentionedflexible insulating film.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view illustrating an embodiment in which the displaypanel and an external drive circuit have been electrically connectedaccording to the connecting method of the present invention;

FIG. 2 is a cross section of a connecting unit used in practicing theconnecting method of the present invention;

FIG. 3 is a circuit diagram of a pulse heat tool;

FIGS. 4A to 4D are explanatory views showing the characteristics of thepresent invention on time axes;

FIG. 5 and FIG. 6 are cross sectional views illustrating packagingstructures of film carriers according to the present invention;

FIG. 7 and FIG. 8 are plan views illustrating output scanning directionsof an IC when the film carrier packaging structure according to thepresent invention is used;

FIG. 9 is a cross sectional view illustrating a prior art film carrierpackaging structure employing an anisotropic conductive film;

FIG. 10 and FIG. 11 are plan views illustrating how film carriers arepackaged on a glass substrate;

FIG. 12 and FIG. 13 are plan views illustrating output scanningdirections of an IC when a conventional film carrier packaging structureis used;

FIG. 14 is a plan view illustrating another embodiment of the presentinvention;

FIG. 15 is a cross sectional view schematically illustrating the methodof the present invention; and

FIG. 16 is a cross sectional view illustrating an embodiment betweenconductive layers connected according to the method of the presentinvention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention will be described below with reference to thedrawings.

FIG. 1 is a plan view illustrating an embodiment in which a liquidcrystal panel 14 and an external drive circuit IC 18 are electricallyconnected with each other according to the connecting method of thepresent invention, and FIG. 2 is a cross section of a connecting deviceused in the present invention. In the figures, the numeral 11 denotes ananisotropic conductive adhesive; 12, denotes a film carrier tape; 13,denotes an external circuit electrode; 14, denotes a liquid crystalpanel; 141, denotes a substrate extended from the liquid crystal panel;15, denotes an electrode for connecting the external circuit; 16,denotes a heat tool; 17, a heating electric source; 18, denotes an IC;19, denotes a bonding member; and 20, denotes an adhesive.

In the present invention, the anisotropic conductive adhesive isprovided between the external circuit electrode 13 of the film carriertape 12 and the external circuit connecting electrode 15. The adhesiveis pressed by means of the heat tool 16, followed by the application ofa voltage to the heating electric source 17 of the heat tool 16 toeffect thermocompression bonding. Thereafter application of the voltageof the heating electric source 17 is stopped and then the pressing bythe heat tool 16 is released. To repeat the above operation, a pulsevoltage is applied from the heating electric source 17 to the heat tool16.

FIG. 3 is a circuit diagram of the heat tool 16, wherein the numeral 31denotes a pulse heat tool; 311, denotes a thermoelectric couple; 32,denotes a trans; 33, denotes a trigger control system; and 34, denotesan AC electric source. In a preferred example of the present invention,the controlling of the trigger control system makes it possible tooutput to the heat tool 31 a voltage of pulse width of 4 msec and ±1 Vwith a frequency of 100 Hz.

FIG. 4A shows the temperature (Ta) of the anisotropic conductive film 11at the time of thermocompression bonding, and FIG. 4B shows the pressureloading (P). More specifically, once the pressing is started, heating iseffected by means of the pulse heat tool to raise the temperature fromroom temperature (about 23° C.) to T₂ (about 130° C.). After t₁ (about20 seconds), the application of voltage to the pulse heat tool 16 isstopped and air blowing is carried out, whereby the temperature isdropped to T₃ (about 60° C.) after t₂ (about 25 seconds), and thepressing by the pulse heat tool 16 is terminated at this point in time.The temperature T₂ is set at such a temperature that the anisotropicconductive film 11 can be sufficiently melted, and the temperature T₃ atsuch a temperature that a sufficient bond strength can be obtained. FIG.4C shows the connection resistance value (R) observed at this time, andis seen to be kept stable both after termination of the heating andafter termination of the pressing.

FIG. 4D shows data on the temperature (Tb) of a display area of aferroelectric liquid crystal display device at a site nearest to theconnecting area (5 mm distant), according to which T₄ was found to be40° C.

The anisotropic conductive adhesive 11 used in the present inventioncomprises a film formed of a thermoplastic resin containing conductiveparticles dispersed therein, and can be formed into a cured materialunder given conditions for heat-curing. As the particles of conductivematerials used here, there can be used particles having goodconductivity, comprising particles of metals or alloys such as Ni, An,Ag and soft solder, or spherical resin particles coated with Au, Ni,etc. Also, usable as this spherical resin particles are those having alinear expansion coefficient substantially equal to that of curableresins. These conductive materials are contained in the proportion offrom 0.5 to 50 parts by weight, preferably from 5 to 20 parts by weight,based on 100 parts by weight of the solid content in the curable resin,and have an average particle diameter of from 5 to 50 μm, preferablyfrom 10 to 30 μm.

Usable as the thermoplastic resin used in the present invention arehot-melt resins such as a styrene/butadiene copolymer, terpene phenolresins, acrylic rubbers, epoxy resins, polyvinyl phenols, anacrylonitrile/butadiene copolymer, phenol resins, polyester resins andnylon. In the present invention, these resins can also be used alone orin combinations of two or more kinds. Besides the thermoplastic resins,it is also possible to use thermosetting resins such as epoxy adhesives,thermosetting silicone resins and thermosetting polyimide resins.

FIG. 16 is a cross sectional view illustrating the structure at amutually connected area according to an embodiment of the presentinvention, where a conductive material pattern 57 of a film carrier andan electrode 59 of a glass substrate 58 are mounted face-to-face, andelectrically connected through conductive particles 161 of theanisotropic conductive adhesive. The adhesive of the anisotropicconductive adhesive and the insulating adhesive are filled in therespective spaces in the form of an integral layer, so that theelectrical connection can be retained and also the connection areas canbe protected from the open air.

As described above, the employment of the anisotropic conductive filmformed in the shape of a film by dispersing and mixing the conductiveparticles in the thermoplastic resin or thermosetting resin makes itpossible to suppress the process temperature to a temperature not morethan the phase transition temperature of ferroelectric liquid crystals,and thus it has become possible to make connection without causing anyorientation disorder during the process of connecting film carriertapes.

Also, by thermocompression-bonding using the pulse heat tool and byrelease of a pressure of the tool after the pulse voltage applicationwas stopped and the tool was cooled, the connection resistance has beenmade stable and the connection reliability has been improved.

FIG. 5 is a cross section illustrating a packaging structure of filmcarriers according to the present invention, where, for example, copperfoil 53 of 35 μm thick is bonded with a bonding material 52 to aflexible insulating film 51 comprising polyimide (as exemplified byUpilex S available from Ube Industries, Ltd.) of 75 to 125 μm thick, anda conductive material pattern is formed thereon by etching.

This conductive pattern is formed in such a manner that it extends up toa device hole 55 to form a finger-shaped inner lead-bonding area 56 usedfor bonding with a semiconductor device 54, to which the semiconductordevice 54 is connected by thermocompression bonding or the like using agold bump.

Similarly, a finger-like outer lead-bonding area 61 is formed in themanner it extends from the flexible insulating film 51.

The above outer lead-bonding area 61 and a transparent conductive film59 comprising ITO or the like and being provided on a glass substrate 58of a liquid crystal display device are disposed facing to each otherwith the interposition of an anisotropic conductive film 57 (asexemplified by AC5052 available from Hitachi Chemical Co., Ltd.)comprising conductive particles such as metal particles dispersed in anadhesive, and at the same time another flexible insulating film 62comprising a polyimide (as exemplified by Upilex R; thickness: 7.5 μm;available from Ube Industries, Ltd.) is disposed at an upper part of theouter lead-bonding area 61, and the area 61 and the film 59 are joinedby thermocompression bonding through an insulating adhesive, thusforming a film carrier packaging structure. After the thermocompressionbonding, the flexible insulating film 62 is removed from the outerlead-bonding area 61.

This flexible insulating film 62 may desirably have its area madesubstantially same as the dimension of the anisotropic conductive film57. This flexible insulating film 62 serves to prevent the bondingmaterial for the anisotropic conductive film 57 from being adhered to ahead area of a thermocompression bonding hot press at the time of thethermocompression bonding, and also to prevent the anisotropicconductive film from absorbing moisture after the thermocompressionbonding and lowering the reliability.

Forming in this manner the packaging structure of film carriers makes itpossible to carry out the packaging on the glass substrate 58 in themanner that the front and back surfaces of the whole film carrier 50 arereversed. In FIG. 6, the respective parts correspond to those in FIG. 5.

Accordingly, in the film carrier packaging structure of the presentinvention, in the case that the film carriers 50 are packaged on bothsides of the glass substrate 58 as shown in FIG. 10, the film carriers50 to be packaged on the left side of the glass substrate 58 in FIG. 10can be packaged in the manner as shown in the cross section of FIG. 5and the plan view of FIG. 7, and the film carriers 50 to be packaged onthe right side can be packaged in the manner as shown in the crosssection of FIG. 6 and the plan view of FIG. 8.

Here, in FIG. 7 and FIG. 8, considering the scanning direction of theliquid crystal picture element driving output of the driving IC 71, itis scanned in the direction of an arrow from 1 in a conventional mannerin FIG. 7, but in FIG. 8 the film carrier 50 is packaged in the mannerthat it has been reversed as will be clear from the figure. Accordingly,even if the driving IC 71 and film carrier 50 of the same type are used,the liquid crystal picture element driving output is scanned in thedirection of the arrow from 1 as shown in the figures, and the packagingon the right and left of the glass substrate may not result in thechange of the scanning direction.

Also, in the film carrier packaging structure of the present invention,the flexible insulating film 62 of the outer lead-bonding area 61 is, asdescribed previously with reference to FIG. 5, bonded to the outerlead-bonding area 61 without using an adhesive, and if there is used afilm which is thin enough to allow taking no account of the thermalexpansion, it may not occur that the slippage or stress is produced inthe anisotropic conductive film.

In the present invention, also used for the thermocompression bondingarea is the flexible insulating film 62 which is sufficiently thinnerthan the flexible insulating film 51 used for the film carrier 50.Accordingly, thermal energy from the heating head of thethermocompression bonding hot press may be readily transmitted to theanisotropic conductive film so that the heating temperature can becontrolled relatively with ease and the thermocompression bonding can becarried out in a short time.

In the above examples, a description has been provided on the filmcarriers and the glass substrate of a liquid crystal display device.However, without limitation to the liquid crystal display device, thepresent invention can be similarly applied also to the driving-ICpackaging in thermal heads for continuous length, close contact typeimage sensors, EL display devices, etc.

The method in which the thermocompression bonding is carried out withthe use of another flexible insulating film sufficiently thinner thanthe flexible insulating film can also be used not only for the outerlead-bonding area of the film carriers, but also for the bonding ofother flexible substrates employing flexible insulating films with glasssubstrates or printed boards made of glass epoxy phenol or the like.

FIG. 14 illustrates another example in which the present invention isapplied to a close contact type image sensor. Also in the case that ICsare packaged by use of a film carrier in conventional direct contacttype image sensors, they can only be packaged in a density of about 5lines/mm (200 μm pitch) if the outer lead-bonding is carried out withuse of the anisotropic conductive film, as mentioned in the aboveexample, and therefore it has been impossible to increase the density atsensor areas so much. However, as shown in FIG. 14, the density atsensor areas can be increased by packaging ICs on both sides of a glasssubstrate, according to the present invention.

In FIG. 14, the numeral 81 denotes a wiring substrate (glass substrate);and 82, a sensor area.

As described above, employment of the film carrier packaging structureaccording to the present invention makes it possible to package the filmcarriers in the manner that the front and back surfaces thereof arereversed, by using the semiconductors and film carriers of the sametype, so that the packaging can be carried out on the substrate to whichthey are bonded, without any change of the scanning direction of theoutput.

Accordingly, the production cost of IC is not increased and a packagingprocess of the film carrier is not complicated. Since there may occur noslippage or stress to the anisotropic conductive film owing to thedifference in thermal expansion coefficient between the flexibleinsulating film and glass substrate, the present invention facilitatesan improvement in the reliability of the connecting sites.

Also since, thermal energy can be readily transmitted from thethermocompression bonding hot press to the anisotropic conductive filmat the time of the thermocompression bonding, it follows that thethermocompression bonding temperature can be controlled with ease andthe thermocompression bonding can be carried out in a short time.

FIG. 15 is a cross section illustrating an embodiment of the presentinvention, according to which, between a glass substrate 58 and a filmcarrier comprising a conductive material pattern (a conductive film)formed in the shape of a finger by removing a base film 51 and anadhesive 52 at an outer lead-bonding area (a conductive material portionnot supported by the substrate), an anisotropic conductive adhesive (afilm), 57 thinner than the thickness of said conductive pattern 53, isplaced. Also an insulating adhesive 152 is placed at an upper part of afilm carrier tape, followed by thermocompression bonding by means of aheated heat tool 159 to make the connection.

The flexible insulating film 62 is used for preventing the insulatingadhesive 152 from being adhered to the heater tool 151 to stain thesurface of the tool.

As to insulating resins used in the anisotropic conductive adhesive 57and insulating adhesive 152, it is desirable to use those having thesame composition, and there can be used hot-melt resins such as astyrene/butadiene copolymer, terpene phenol resins, acrylic rubbers,epoxy resins, polyvinyl phenols, an acrylonitrile/butadiene copolymer,phenol resins, polyester resins and nylon, etc. In the presentinvention, these resins can also be used alone or in combinations of twoor more kinds. In the formation of films, it is also possible to useconventional coating methods as exemplified by roll coating, printingand spray coating, and solvents for coating solutions used in thatoccasion include toluene, methyl ethyl ketone, ethanol, xylene, etc.which are used alone or as a mixed solvent thereof.

The thickness after being dried, of the insulating adhesive 152 used inthe present invention is set to range from 5 μm to 50 μm, preferablyfrom 15 μm to 30 μm, and the thickness after being dried, of theanisotropic conductive adhesive 57, is in the range from 1 to 25 μm,preferably from 5 to 15 μm, approximately. In the laminated structure ofthis insulating adhesive 152 and anisotropic conductive film 57, it maypreferably be set in the range from approximate 10 to 100 μm, preferablyfrom 20 to 50 μm.

A film carrier tape was comprised of a polyimide film (thickness, 125μm) to which electrolytic copper foil (thickness, 35 μm) adheres, andwhich is subjected to patterning. At the outer lead-bonding areathereof, it was formed in the form of a finger by removing the polyimidefilm. The conductive material pattern was polished on its adheringsurface and treated with Ni-Au plating to have a thickness of about 30μm. Here, wiring pitch was set at 100 μm; the conductive material width,at 50 μm; and the conductive material spacing, at 50 μm.

Conductive-material wiring on a glass substrate was made to have awiring pitch the same as that of the film carrier tape, and formed tohave a thickness of 1,500 Å with ITO (ITO: indium-tin oxide).

An anisotropic conductive film 57 used was "AC 5101" (a resincomposition comprising a urethane resin and Au-plated resin particlesdispersed therein) (film thickness, 8 μm) available from HitachiChemical Co., Ltd., and an adhesive using the same resin but containingno conductive particles was formed to have a thickness of 20 μm.

The anisotropic conductive adhesive 57 was placed on the glasssubstrate, and the pattern of the film carrier was registered, andprovisional bonding was effected by pressing for 3 seconds at atemperature of 120° C. and under the pressing condition of 20 kg/cm².Thereafter, an insulating adhesive 152 was placed. Then, with theinterposition of a polyimide film (the flexible insulating film 62) of7.5 μm thick, pressing was carried out for 20 seconds by means of apulse heat tool 151 at a temperature of 150° C. under the pressingcondition of 40 kg/cm², to effect thermocompression bonding.

The bonding area connected by this process had a 90° peel strength of500 g/cm or more and a connection resistance of 100 ohms or less,obtaining good results, and it was able to be confirmed that theouter-lead connection using the film carrier tape and having a highresolution can be achieved with good reliability.

As described above in detail, the mutual connection having a highresolution and strong bond strength, i.e., having a high reliability wasmade possible according to the method in which the thin anisotropicconductive adhesive, i.e., an anisotropic conductive adhesive having ahigh resolution, is placed between the film carrier tape formed in theshape of a finger, having an outer-lead conductive material pattern, andthe glass substrate, and the insulating adhesive is placed on the filmcarrier tape, followed by thermocompression bonding by means of the heattool to make the connection.

We claim:
 1. A film carrier packaging structure comprising:a pluralityof first flexible insulating films having a conductive material patternformed thereon, with each said conductive material pattern having anouter lead-bonding area and an inner lead-bonding area, with said outerlead-bonding area extending from said first flexible insulating films inthe shape of a finger, wherein an inner lead-bonding area of one of saidfirst flexible insulating films connects with a first semiconductordevice disposed in a face-up state and an inner lead-bonding area ofanother one of said first flexible insulating films connects with asecond semiconductor device disposed in a face-down state; a wiringsubstrate having an anisotropic conductive film disposed thereon, withan outer lead-bonding area of one of said first flexible insulatingfilms being disposed on said conductive film and facing said wiringsubstrate; and a second flexible insulating film thinner than said firstflexible insulating films and being disposed on said outer lead-bondingarea of said one of said first flexible insulating films, wherein saidsecond flexible insulating film is heated to thermocompression-bond saidouter lead-bonding area to said wiring substrate.
 2. The packagingstructure of claim 1, wherein a conductive foil of said outerlead-bonding area has a thickness substantially equal to the sum of thethickness of said second flexible insulating film and the thickness ofsaid anisotropic conductive film.
 3. A display apparatus comprising:adisplay device including a first display substrate having a first groupof electrodes and a first group of terminals connected with said firstgroup of electrodes, a second display substrate having a second group ofelectrodes intersecting said first group of electrodes and a secondgroup of terminals connected with said second group of electrodes, and adisplay material disposed between said first and second displaysubstrates; first and second film carriers comprising first conductivefilm portions fixed on said carriers and second conductive film portionsextending from said carriers; a first semiconductor element electricallyconnected with said fixed conductive film portion on said first filmcarrier in the face-up state, and a second semiconductor elementelectrically connected with said fixed conductive film portion on saidsecond film carrier in the face-down state; and a first anisotropicconductive member disposed between said first group of terminals andsaid conductive film portion extending from said first film carrier, anda second anisotropic conductive member disposed between said secondgroup of terminals and said conductive film portion extending from saidsecond film carrier.
 4. A display apparatus of claim 3, furthercomprising insulating members disposed on said extended conductivematerial film portions extending from said first and second filmcarriers.
 5. A display apparatus according to claim 3, wherein saiddisplay material is a liquid crystal.
 6. A display apparatus accordingto claim 5, wherein said liquid crystal is a ferroelectric liquidcrystal.
 7. A film carrier packaging structure comprising:a plurality offirst flexible insulating films having a conductive material patternformed thereon, with each said conductive material pattern having anouter lead-bonding area and an inner lead-bonding area, with said outerlead-bonding area extending from said first flexible insulating films inthe shape of a finger, wherein an inner lead-bonding area of one of saidfirst flexible insulating films connects with a first semiconductordevice disposed in a face-up state and an inner lead-bonding area ofanother one of said first flexible insulating films connects with asecond semiconductor device disposed in a face-down state; and a wiringsubstrate having an anisotropic conductive film disposed thereon, withan outer lead-bonding area of one of said first flexible insulatingfilms being disposed on said conductive film and facing said wiringsubstrate.